Starbucks Corp., the world’s largest coffee-shop operator, will match US employees’ contributions to their 401(k) retirement plans after earnings improved, Chief Executive Officer Howard Schultz said in a memo.

The Seattle-based company said in December that it may not match funds contributed by its employees this year as earnings fell amid tighter consumer spending. The company yesterday told employees it will also award merit-based salary increases and warned of higher health-care costs.

“Our progress over these past few months has given us the opportunity to fund the company discretionary match for the 2009 plan year,” Schultz said in the memo to workers. “Make no mistake, we remain humbled by the uncertain economic environment and know we have a long journey ahead.”